


Show Me More Of This Strange Earth Custom You Call "Kissing"

by TheseusInTheMaze



Category: Doctor Who (2005)
Genre: Consent Play, Cunnilingus, F/F, Female Ejaculation, Finger Sucking, Fingering, Kissing, Medical Kink, Vaginal Sex, strap on
Language: English
Status: Completed
Published: 2020-01-10
Updated: 2020-01-10
Packaged: 2021-02-27 08:49:01
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 6,571
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22194322
Author URL: https://archiveofourown.org/users/TheseusInTheMaze/pseuds/TheseusInTheMaze
Summary: "So I've been having... fantasies, you know how it is, you have daydreams while having a wank that kinda just show up in your head out of nowhere and then you're having an orgasm and you don't know where it came from but it's still nice, only next time you're wanking it's the first thing to pop into your head?" The Doctor was waving her hands about."Um," said Yaz. "Can't say that I've really had that experience, no."
Relationships: Thirteenth Doctor/Yasmin Khan
Comments: 19
Kudos: 166





	Show Me More Of This Strange Earth Custom You Call "Kissing"

**Author's Note:**

> I had to title it that, after three different people made that joke at me when I told them the plot of this fic.

“How do you figure out your sexual proclivities?” The Doctor said it casually, but Yaz still knocked over the glass of water she had been pouring. “Oh no, look at that mess, lemme get you a towel there, Yaz.” 

“Um,” said Yaz. “What was… um.” She coughed, put her glass down, and then she was blushing harder as the Doctor dabbed at her lap with a tea towel. It was embroidered with little dancing capybaras. 

“Sorry, was I doing that thing again?” The Doctor looked up at Yaz, all big hazel eyes and concerned expression, and it _really_ wasn’t fair that she was that cute. 

"Which thing?" Yaz poured herself another glass of water, and didn't spill this time. "You have a lot of things, Doctor." She _seriously_ needed to stop blushing.

"The thing where I say something awkward and you're too embarrassed to say anything about the fact that I've said something awkward, so you just let me keep talking until I start losing steam." The Doctor was standing very close to Yaz, and she looked nervous. She was twisting her fingers together, and it was making Yaz's own knuckles ache in sympathy. 

"I mean," said Yaz, and she tried to keep her tone light, "I kinda gave up on you ever running out of steam." She tucked a piece of the Doctor's hair behind the Doctor's ear, and the Doctor smiled at her, eyes crinkling up at the edges. 

"I'm sure I will eventually," said the Doctor. Her hands hovered over Yaz's hips, then rested there, delicately. Her fingers hooked into the belt loops of Yaz's jeans, and Yaz sighed, leaning closer, until they were forehead to forehead.

This sort of closeness was still new to the two of them. The Doctor was as skittish as a feral cat, and half the time she'd dash off at the first sign of any kind of intimacy, babbling a mile a minute. She'd gotten better about it, at least. 

"I'm still figuring myself out," the Doctor said, and her breath was warm across Yaz's face. "The me I am now, I mean. I've still got some of the same interests that I used to have, obviously, but I've also been realizing I've got some other interests, or maybe they're the same interests, only they're shaped differently because _I'm_ shaped differently." 

"That makes sense," said Yaz. "I mean... plenty of people's... sexual interests change as they get older. Let alone if they... change to the degree that you change." She draped her own arms over the Doctor's shoulders, and pressed a little closer. She tried to ignore the unhelpful part of her mind that was telling her that they looked like primary school kids attempting a slow dance. 

"Thanks, Yaz," said the Doctor, and she rubbed their noses together. She was grinning widely, and she looked faintly dopey. It was endearing, but dopey was a look that suited the Doctor. 

It was a good thing, too, considering how often she wore that look. 

"So what's your new interest?" Yaz let her hands move to the back of the Doctor's neck, gently ruffling the short hairs there. "If you're comfortable telling me, I mean."

"I trust you won't judge me too badly," said the Doctor. "I mean, maybe you will, but I can't exactly tell you not to judge me, since it's your head. But, um." She licked her lips, then disentangled from Yaz, to begin pacing around the small kitchen. 

Yaz leaned against the lip of the kitchen table, and she crossed her arms over her chest, watching the Doctor make a circuit around the little island in the middle of the kitchen, then pause, to turn to look at Yaz. Her coat was flowing out behind her like a superhero's cape.

"So I've been having... fantasies, you know how it is, you have daydreams while having a wank that kinda just show up in your head out of nowhere and then you're having an orgasm and you don't know where it came from but it's still nice, only next time you're wanking it's the first thing to pop into your head?" The Doctor was waving her hands about. 

"Um," said Yaz. "Can't say that I've really had that experience, no." She had been known to go down some... unexpected routes while masturbating, but nothing too outlandish. 

"Okay," said the Doctor, and then she stopped pacing to turn and look directly at Yaz. "You know how there's all these rumors on Earth and about aliens abducting people and probing their bums and stealing their cows?"

"Yeah?"

"I wanna do something like that. Sexually. Only without the cattle. Although I suppose I'd be okay if you wanted me to wear a cow costume, I've probably still got -"

"You want to abduct me and probe my bum?" Yaz was trying to keep up. At least that was familiar footing. 

"I mean, yes, I'd love to do that too, but that wasn't _exactly_ what I was thinking of," said the Doctor. "I was more thinking of, uh, of..." She paused, and she was rubbing her hands together again, avoiding eye contact with Yaz. "Well."

"Well?"

"Well," said the Doctor. "Y'see, it's more like..." She made another expansive hand gesture. "Y'know?"

"... No," said Yaz. "Could you give me an example?"

She liked the way the Doctor blushed. “I could try,” she said, and she looked downright _bashful_.

God, it was adorable.

* * *

“So,” said the Doctor, some time later. 

Yaz wasn’t sure how long it had been, since time got weird when they were on the TARDIS. They’d been parked in the Time Vortex for a bit, recovering from a particularly… adventurous adventure. Graham and Ryan were parked in one of the personal movie theaters around the place. They were probably getting in some good old family bonding time. Or possibly arguing, knowing those two. 

“So,” Yaz echoed. 

“I’ve got a whole wardrobe full of costumes,” the Doctor said. “Go pick something out that looks suitably… fitting the role.” She paused, fidgeting. “Do you want me to wear anything specific?” 

“I think your usual outfit will do,” Yaz said, and she was trying very hard not to start giggling. This was all a bit… silly.

“I feel like you’re making a comment on my fashion sense,” said the Doctor, “but I’m not exactly sure.” 

“It’s a human joke,” Yaz said, trying to sink into the role. “Don’t worry about it.”

“Ooo, that’s a good ‘un. You’ve really got the tone down, thank you!” The Doctor was practically _bouncing_ now. “I’ll go wait in the room for ya!” 

“You do that,” Yaz said, her tone only a little distant.

“You’re okay with this, right?” The Doctor paused, and she was frowning at Yaz, her expression concerned. “Unless this is too weird for you?”

“No, no,” Yaz said quickly. “No, this isn’t too weird. I promise. It’s great.” She cupped the Doctor’s cheek, her thumb against the Doctor’s cheekbone, and then she leaned forward and kissed the Doctor on the mouth, a quick little peck.

The Doctor was blushing, and she was grinning wide. “You’re brilliant, you are,” she told Yaz, and she was practically _skipping_ as she made her way off to whatever room it was that she had planned this all for. 

It wasn’t that she’d never done this kind of role play before. The last person she’d dated had asked her to wear her uniform in the bedroom, but that had been a bit too weird. This, at least, was far enough removed from her day to day life.

Inasmuch as she _had_ a day to day life these days. 

She wandered around the huge wardrobe room, eyeing all the… everything. The Doctor seemed to have amassed a whole movie set’s worth of stuff. Yaz spent a whole fifteen minutes trying to find whatever it was she was looking for. She wasn’t even sure what it was she was looking for. 

Eventually, she settled on a lab coat and a clipboard. Couldn't really go wrong with a clipboard, right? She added something else on a whim, but… well, she had a feeling the Doctor wouldn’t mind too much. 

* * *

The Doctor was sitting in what looked like an exam room. There was an exam table and a big cabinet, as well as a sink. The Doctor was sitting on the exam table, swinging her feet. She had left her coat draped over one of the chairs pressed against the wall, and she looked nervous. Her whole face lit up when she saw Yaz, and she smiled widely. 

"You look proper official," she told Yaz. 

"I do my best," Yaz said, and she cleared her throat. "So," she said, and she did her best to sound official, "you were brought here because one of our agents found you wandering around."

"Complicated planet you got here," the Doctor said, chipper as ever. "I thought I'd done my research, but I ended up getting _incredibly_ lost." She was fiddling with her fingers, and her eyes kept darting around. 

"Were you tested before you came to Earth?" Yaz tapped her fingers on the clipboard, trying to look official. Maybe this would have been easier to do if she had been wearing glasses as well. And she'd forgotten a pen. How did she have a clipboard and not a pen?

"Tested?" The Doctor frowned, and she stared up into Yaz's face, the very image of a clueless innocent. Considering the Doctor was rarely either of those things, it was a bit surreal to see on her face. Although she wore it pretty well. No wonder she'd been able to get away with who knew what over all the years.

"Tested, to make sure you're safe to Earth?" Yaz crossed her arms, and she attempted to glare. "Whether you know our customs, whether you have any unsafe organisms on your skin or in your body."

"Oh," said the Doctor. She looked faintly surprised. "I mean, I got an at home kit -"

"An at home kit won't cover everything," Yaz interrupted, before the Doctor had a chance to finish what she was saying. "I'll have to do the test myself." 

"Well, I'm happy to help," the Doctor said, as cheery as ever. She was still fiddling with her fingers. "Erm. Submit? To be tested."

"Right," said Yaz. She was a bit at a loss, and the Doctor was looking up at her expectantly. "I've got special... nanites embedded in my fingers," said Yaz, putting the clipboard on the table. "They're going to be able to test to see if you've got any harmful organisms on your skin."

"Oo, that's a good one, Yaz," the Doctor enthused. "I wouldn't have thought of that!"

Yaz snorted. "It's hard to stay in character when _you_ can't stay in character," she told the Doctor.

"Sorry," the Doctor said, and she looked as sheepish as she was able. "You're just doing such a good job!"

"I do appreciate it," said Yaz, and then she cleared her throat. "So," she said, and she was trying to get back into character. "I'm going to start testing your skin now."

"Right," said the Doctor, shivering as Yaz's fingers stroked along the line of the Doctor's jaw, then over the ear cuff. Yaz’s fingers found the soft spot behind the Doctor's ear, and she swirled her finger just to watch the Doctor shudder. "I've always been curious about Earth," the Doctor said, her tone keen enough to cut mustard. “You just have such _fascinating_ customs!” 

"Do we?" Yaz let herself enjoy the sensation of the Doctor's skin under her fingers. It was so _soft_ , and she liked the way that the Doctor was trembling. 

"Oh yes," said the Doctor, and she shivered again as Yaz's fingers slid through her scalp. "I've always had an interest in exotic alien planets, and after I watched several of your Earth cultural documentaries, like _Debbie Does Dallas_ -"

"Doctor," Yaz interrupted, and she was trying not to start laughing. "Please don't mention porn when I'm trying to be serious. Especially porn that's older than I am."

The Doctor paused, and Yaz pressed her thumb against the Doctor's lower lip. "Is it that old?"

"It's fairly old," said Yaz, and then she slipped her thumb into the Doctor's mouth.

The Doctor sucked on it, and the tip of her tongue traced over the very tip of Yaz's fingernail. She looked entirely too good like that, and Yaz's stomach clenched sweet and deep. _Fuck_. 

"I need to make sure there isn't anything harmful in your mouth," Yaz said. "Because there may be some kind of harmful bacteria you're carrying."

The Doctor nodded, and she opened her mouth a little wider. 

Yaz let her fingers explore the inside of the Doctor's mouth. It was hot, wet, and velvety. The Doctor was staying very still, and that was... a lot. The Doctor was almost never still, and that was enough to make Yaz's heart beat a little faster. She pressed her index finger down on the Doctor's tongue, and the Doctor made a quiet little noise. 

The Doctor had some drool down her chin, and her expression was slightly spacey. She was beginning to squirm again, and Yaz licked her lips, withdrew her fingers. "I'm going to need to check a little more thoroughly," she told the Doctor. "I've got nanites in my mouth as well, so I'm going to use that against your mouth."

"Are you sure?" The Doctor frowned. "This wasn't in any of the things I studied.” 

"Do you not trust me?" Yaz put on her best stern face, trying to channel one of her superiors on the force. “I can assure you, our agency is completely legitimate.” 

The Doctor opened her mouth to say something - maybe compliment Yaz on the framing device again? - and then closed it. “Alright,” she said, meek as anything. 

Yaz leaned down, and she kissed the Doctor on the mouth. It was a light, gentle kiss at first, like something out of the romance novels that Yaz's grandmother liked to read. Then Yaz deepened the kiss, her hands going to the Doctor's face. Her thumbs rested on the Doctor's cheekbone, and the Doctor sighed, a rush of hot air across Yaz's own cheek. Her hand came up to rest on Yaz's cheek. 

Yaz pulled back. "You need to keep your hands to yourself," she told the Doctor, and her voice was only shaking a little bit. This felt like it… fit, for lack of a better way of putting it. She couldn't imagine being some invasive scientist taking advantage of a naive alien if she was kissing the Doctor like her lover. 

"I'm sorry," the Doctor said, and she sounded it. "I didn't mean -"

"This is an important investigation," Yaz said, "and I don't want you possibly contaminating me."

"Right, right," the Doctor said quickly. "Sorry."

"Just don't do it again," Ysz said, and she tried to keep her tone stern. She leaned forward, and she kissed the Doctor again, her tongue swiping against the Doctor's, then sliding along the line of the Doctor's teeth. She tangled her fingers in the Doctor's hair and forced the Doctor's head back, so that her tongue could go deeper into the Doctor's mouth. 

The Doctor was shuddering, as Yaz sucked on her tongue, then licked into her mouth. When they pulled apart again, her eyes were dark and she was panting. Her lips were swollen from all of the kissing. She looked like a debauched dream, and Yaz pressed her thighs together. _Fuck_. 

"Am I… am I safe? I wouldn't want to hurt a human on accident." The Doctor licked her lips, and Yaz could swear that she could almost feel it against her skin. She wanted to press closer to the Doctor, wanted to kiss her again. 

"I'm not sure," said Yaz. "I need to test again." She kissed the Doctor harder this time, and Yaz used her teeth this time, nibbling on the Doctor's lips, sucking on her tongue, licking into the Doctor's mouth. She let her hands roam, untucking the Doctor's t-shirts to run her fingers across the flat, smooth plane of the Doctor's belly. She pushed the braces off of the Doctor's shoulders. 

"Are you still ch-checking me?" The Doctor was actually _trembling_ \- how much was she into this fantasy?

"Humans are very touch oriented," Yaz said, and her hands moved up, pushing up the cups of the Doctor's bra. Her hands made lumps under the fabric. "If you want to fit into society, you need to let people touch you. Whenever they want. However they want to." She held the Doctor's small breasts in her hands, flicking the Doctor's nipples. 

"I've n-never seen humans do this with… with each other," the Doctor said, and her voice was hitching. Her hearts were beating desperately against Yaz's palms. 

"It's because humans can tell that you're not human," said Yaz. She pushed the Doctor's shirt up over the Doctor's breasts, and the Doctor's nipples were already starting to pebble in the cooler air of the room. "You want to be treated like a human, don't you?"

“Yes, I suppose you’re right,” said the Doctor.

“I need to check your skin for more microbes,” said Yaz, and then she was leaning down, kissing along the curve of the Doctor’s breast, then taking it into her mouth. She could feel the Doctor’s hands shaking next to her - the Doctor wasn’t touching her, wasn’t grabbing her. The Doctor was being very good, and keeping her hands to herself. 

Yaz had to admit, there was something intoxicating about getting to touch the Doctor, while the Doctor couldn't touch her. She wasn't distracted by the Doctor's warm fingers finding all of the good places that took her off track. It was nice, to greedily take in the Doctor's body. 

The Doctor's nipple was hard against Yaz's tongue, and the Doctor seemed to go stiffer as Yaz took more of the Doctor's breast into her mouth. Yaz sucked, her other hand kneading the Doctor's other breast, and the Doctor gasped. 

Yaz pressed her cheek into the space between the Doctor's breasts, and she pressed her ear into the Doctor's sternum, listening to the sound of the Doctor's hearts. She twisted the Doctor's wet nipple between two fingers, and she listened to the Doctor's hearts speed up. 

"This is… this is a human thing?" The Doctor's voice echoed through Yaz's head, and Yaz turned her head, pressing kisses along the Doctor's other breast, towards her nipple. Thankfully she had tied her hair back - it would have been sticking to her sweaty skin by now, or to the Doctor's. 

"It's one of them," said Yaz, before sucking on the Doctor's other nipple, rasping along the tip with the flat of her tongue. She used her teeth, gently, and the Doctor froze, then went almost liquid.

 _Interesting_. 

Yaz bit the Doctor again around her nipple, a little harder this time, and then she sucked, alternating the pressure. The Doctor was still trembling, and when Yaz stood up again (her back was starting to complain) she saw that the Doctor's knuckles were white as she gripped the edge of the table. She kept her eyes on the Doctor's face and she twisted the Doctor's nipples hard, the way the Doctor sometimes did with the instrument panel of the TARDIS. 

The Doctor gasped, her eyes squeezing shut, then popping open again to stare into Yaz's. "That… it hurts," she said, and her voice was hoarse. 

Yaz pulled her hands away from the Doctor's breasts, concern immediately overriding her arousal. "I'm sorry," she said in a rush. "Do you want me to -"

"Is the pain a sign I'm not fit for Earth?" The Doctor interrupted. Her cheeks were very pink, and her nipples were darker, puffy from the pinching and the sucking. "Because I can take it."

Well, That was pretty blatant. 

Yaz pinched the Doctor's njpple again, and ran a hand up the Doctor's inner thigh. "I need to check something, if that's the case," and she kept her tone as bland as possible. The Doctor's legs were spreading wider, and her inner thighs were pressing against Yaz's hips. 

"Of course," said the Doctor. "Anything for you. For this," she corrected quickly. "Anything to assure you. I wanna do all the planet things to do on Earth, be a tourist. Gotta be prepared for that." 

There was something deeper in what the Doctor was saying, something intense that made Yaz's stomach leap. She would probably need to talk to the Doctor about that at some point. Some point that wasn't now. 

"I'm gonna need to take your pants off," said Yaz, trying to keep her tone stern. “I know your species has a specific reaction to stress, and I need to check.”

"There isn't a specific reaction to stress that I know of," the Doctor frowned. "Unless... ooo, Yasmin Khan, you are _devious_!"

"Doctor," Yaz scolded, although she was trying not to start laughing. 

"Sorry, sorry," the Doctor said. "I'm horrible at staying in character." She wriggled, her feet, clearly delighted. "It's just you're being so stern and so objectifying and it's -"

Yaz covered the Doctor's mouth with one hand, and she tried to channel her must grumpy inner cop. "I need to check you for this stress reaction," Yaz said firmly. "Or else I'm going to have to take special measures."

"Wouldn't want special measures," the Doctor agreed, her voice only a little muffled. Her mouth was moving against Yaz's palm, and it was making Yaz break out in goosebumps. 

"Get off the table and bend over it," said Yaz. "I'm going to examine you."

"Right," said the Doctor. She licked her lips, and her tongue passed over Yaz's palm again. 

Yaz let go of the Doctor, and she took a step back, giving the Doctor space to get down off of the table. Her heart was in her throat as she watched the Doctor bend over the table. 

"Much better," said Yaz, and she rubbed her hands together, then grabbed the Doctor's ass. She squeezed it, and the Doctor made a muted little noise. 

"I know that your species can... release dangerous chemicals when under stress," Yaz said, and she was only floundering a little. She should have planned this better - it was harder to come up with these ideas on the fly. "Take your pants down."

"Right," the Doctor said, and Yaz watched, transfixed, as the blue fabric slowly slipped down the Doctor's thighs, baring her underwear to the room. She was wearing boxer shorts printed with multicolored question marks, and Yaz could see the fabric soaked at the crotch. 

"Are you stressed right now?" Yaz licked her lips, and she let her hands roam to the Doctor's ass, giving it a squeeze. She used both hands to spread the Doctor's thighs open, and the Doctor... let her. 

_Fuck_. 

"Little nervous, won't lie," the Doctor said, and there was a slightly manic note to her voice, as if she was forcing the chipper tone. "I think getting examined like this makes anyone a little - _oh_!" 

Yaz had reached between the Doctor's legs and grabbed her vulva, squeezing it. Her middle finger was forcing the thin cotton up against the Doctor's labia, and the Doctor was shuddering. 

"You're producing a lot of... it looks like a stress reaction," Yaz said, and her voice was hoarse. Her fingers found the leg hole of the Doctor's boxers, and she slid her fingers inside. 

The Doctor was so wet that Yaz's fingers almost immediately began to prune up. She was shaking, and she gave a muted gasp when the tip of Yaz's index finger found her clit. Her hips twitched forward. 

"You seem very stressed," Yaz said, keeping her tone very stern. "How do I know you'll be safe for human beings?" She pressed a finger into the Doctor's cunt, and she bit back her own moan at the tight, wet squeezing. 

"I'm... safe," the Doctor said, and she made a desperate noise when Yaz's finger curled inside of her. She was full on _humping_ back against Yaz's hand now.

"Stay still," Yaz said sharply, and the Doctor froze. She gave a little whimper when Yaz's fingers withdrew, and she shuddered when Yaz shoved the boxers down, leaving her naked from the waist down. The Doctor's shirt had fallen back down her back, and there was something almost indecent about that sight - the hems of the two t-shirts, brushing against the very top of the Doctor's bare ass. 

The Doctor moaned when Yaz's fingers pressed into her. She was smooth inside, hot and slippery. The sound of Yaz's fingers sliding in and out was _obscene_ , and it seemed to fill the whole room. 

"Are you sure this isn't a stress response?" Yaz curled her fingers, found the spot that changed in texture, and the Doctor made a muffled noise. She must have been covering her mouth, not wanting to get told off again. "I can see that you're tensing up."

"Not a stress response," the Doctor said. Her voice was rough. 

Yaz watched her own hand, fingers pressed between the Doctor's legs. She twisted her fingers, and the Doctor cried out. The Doctor's knees were shaking, and Yaz could see the way her skin was turning pinker. 

If not for the double pulse around her fingers, Yaz might have been fucking a human woman. Their species really were similar, weren't they?

 _I'm having sex with an alien_ , went through Yaz's mind, and that made her shiver. It wasn't the first time she had done this with the Doctor, wasn't the first time she had the thought, but it still made her head spin every time. She added a third finger, and the Doctor made another needy sound. The Doctor's cunt was clutching Yaz's cunt like it never wanted Yaz to leave, and then Yaz was reaching her other hand around, to rub the Doctor's clit with the tip of her index finger. She liked the way the Doctor seized up against her, liked the way the Doctor's cunt gushed out more wetness. 

"You seem very stressed," Yaz said, as she thrust and rubbed, letting the musky, deep scent of the Doctor's arousal fill her head. She was so wet herself that she was faintly worried these jeans would be ruined. "I can feel the tension in your body. If you want to fit in on Earth, you need to be used to this kind of handling." Never mind that she had said this was for testing… what had she said it was for testing? She was losing track of her own ridiculous narrative. She wriggled the fingers inside of the Doctor as if she was drumming on the surface of a table and pressed down on the Doctor's clit at the same time. 

The Doctor gasped, and her cunt began to squeeze Yaz's fingers, pulsing rhythmically around them. The Doctor was groaning and gasping, and then she was going limp, her belly flat against the table. She was trembling, and Yaz wished she could have seen the Doctor's face. She always loved watching the Doctor's animated face, and it was never more animated than when she was coming. 

Yaz slowly removed her fingers, and she grabbed the Doctor by the back of the neck with her clean(er) hand. The Doctor leaned into it, making desperate little noises, and she let herself be turned around, so that her back was pressing into the lip of the table. "Care to explain this?" Yaz held up her glistening fingers.

"It's a perfect… perfect… perfectly normal response," the Doctor panted. She looked downright _debauched_ , her lips swollen and her eyes dark. 

"I'm going to have to do more tests," Yaz snapped, and she dropped down on her knees in front of the Doctor. Her hands went to the Doctor's bare hips, and she pressed her face forward, until her nose was nudging along the Doctor's slit. 

The Doctor made an inarticulate noise and jerked forward, pressing more of herself against Yaz's face. The dark hair covering the Doctor's vulva was pasted down with wetness, and it all smelled like sex and desperation. There was something… special about the Doctor's scent, something that always made Yaz's mouth water and her tongue tingle. 

Alternately, Yaz really liked eating pussy. So far, the results were inconclusive. Yaz would have to keep testing. 

Yaz licked along the seam of the Doctor's labia, from her hole up to her clit. She fastened her lips around the Doctor's clit and swirled her tongue, and the Doctor made more muffled noises, trembling. When Yaz looked up, she saw the Doctor's eyes squeezed shut, her whole face tight. She shifted, moving her neck just short of uncomfortable, h her tongue probed between the Doctor's labia. She found the Doctor's entrance and slid her tongue inside, and the Doctor made another desperate noise. 

Yaz kept her eyes on the Doctor's face, as her tongue wriggled inside of the Doctor's cunt. She clumsily pushed her face forward, awkwardly rubbing the Doctor's clit with her nose. The Doctor sobbed, her hand buried in her own hair, forcing her head back. The tendons of her neck stood out, and Yaz wanted to sink her teeth into them. 

She settled for digging her thumbs into the divots of the Doctor's hips, and sucking on the Doctor's clit, flickering her tongue along it. 

The Doctor shuddered against Yaz, and then there was the sensation of the Doctor's inner muscles shuddering, right up against Yaz's face. There was a gush of wetness, and it smeared across Yaz's chin, leaving her sticky and musky. The Doctor’s face opened up like a flower, going ugly and endearing, and something in Yaz’s chest clenched like a fist. 

Yaz pulled back, and she looked up at the Doctor. The Doctor's chest was heaving, and her face was a deep, dark red. "You did it again," Yaz said, and she tried to sound like she was scolding. “I’m going to need a special instrument to check.” 

“Special instrument,” the Doctor said, and she was biting her lip. 

“Unless you… don’t… need…” Was there a way for Yaz to ask the Doctor if she wanted the strap on? Should she have asked beforehand? This stuff was always easier in the dirty books she’d snuck off of her mother’s bedside table. People never had to talk about this stuff. 

“I trust you,” the Doctor said, and she stared up at Yaz with her big hazel eyes, and she licked her lips. They seemed to be having a moment. “I trust you to do what’s right,” said the Doctor. “What’s necessary. For the safety of the earth, obviously. And the humans. All about the safety.” The Doctor licked her lips again. 

_She’s floundering_ , Yaz thought. _Full on flustered. I’m impressed._

“I’m going to have to do a few more tests,” Yaz said, and she tried to sound like she knew what she was talking about. “Get on the table and spread your legs.” 

“Right,” said the Doctor. “What, um, what instrument have you got?” 

“A special one,” Yaz said, and she tried to keep from giggling as she unbuttoned her pants. She pushed them down, and the strap on that had been pressed into her thigh sprang forward. 

“Ooo,” the Doctor said, and her eyes went wide. “That _is_ a special one! Where’d you find that?”

“You’ve got a whole chest full of sex toys in the wardrobe room,” Yaz said, and she wrapped a hand around the base of the dildo, where it rested against her vulva through the harness. “I… found it, and I chose one that, y’know, wasn’t too…” She made a vague hand motion. “Would you have preferred -”

“No, no, that’s a good ‘un,” the Doctor said. “By all means.” She spread her knees open wider. “I don’t think I’ve ever used that one with this body.” She was on the table the long way now, her legs dangling off the end.

“Right,” said Yaz, and she licked her lips. She came around to stand between the Doctor’s spread thighs, her eyes darting between the Doctor’s hot, pink cunt to the Doctor’s hot, flushed face. She brought her hands to the Doctor’s thighs, and she spread them open wider. “I’m going to have to use my… I’m going to have to test you.” 

The Doctor shivered all over. Her nipples were hard through her t-shirts where they had fallen back over her breasts. The bunched up fabric of her bra was lumpy under her shirt, up towards her collar bones. “I’ll submit to any test you need to do,” the Doctor said, and she kept her tone earnest. “I don’t want to put any humans at risk.” 

“Good,” said Yaz, and she grabbed the Doctor by the back of the knees, pulled her closer. The Doctor almost _slid_ on the smooth surface of the exam table. “That will look good on my report.” 

“Report,” the Doctor repeated faintly. She was looking up at Yaz, and she squirmed, her heels digging into the back of Yaz’s thighs. The orange of the dildo was… garish, to be sure, but it looked kind of nice against the hot pink of the Doctor’s cunt. 

Yaz guided the head of the toy in, and she pushed it forward. The dildo got thicker and narrower along the shaft, and Yaz watched it disappear into the Doctor, and then she watched the Doctor’s face. 

The Doctor’s mouth had fallen open, and her head was thrown back. Her hands were clutching at the hem of her t-shirts, and her thighs were tensed up, her heels pressing into the backs of Yaz’s thighs. 

“I’m writing a report,” Yaz repeated, and then the front of the strap on harness was pressed into the Doctor’s vulva. She wriggled her hips, grinding into the Doctor’s clit, and the Doctor made a broken little noise. “Like I do with every alien that I… investigate.” 

The Doctor had a hand at her mouth now, and her teeth were digging into the side of it. She was clenching tightly around the toy, and Yaz half wished she could feel it herself. She ground her hips forward again, and then withdrew a bit, before pushing back in. The Doctor was panting, and she was almost _sobbing_ when Yaz withdrew, then pushed back in. The thicker parts of the dildo must have been stretching her open slowly. 

On a whim, Yaz yanked her hips back, until only the tip of the dildo was inside of the Doctor. Then she shoved her hips all the way forward, almost pushing the Doctor forward on the table. 

The Doctor _squealed_ , and her eyes flew open. She stared at Yaz, rapt, and Yaz leaned forward. She took the Doctor’s hand in her own, and she kissed the palm of the Doctor’s hand, then each finger. She was probably ruining the whole scene, losing her scientific detachment, but she had to do… something with her mouth, had to transmit the hugeness of the emotion that was filling her chest. She kept eye contact as she took the Doctor’s fingers into her mouth, and she sucked on them, her tongue sliding between the index and the middle finger.

“Oh,” the Doctor said, and her voice was rough. “Oh, something’s happening, something is… I…”

Yaz began to thrust in earnest, and okay, this was more tiring than she thought it would be. She was in shape - between her training for the Force and all the running she did with the Doctor - but… still. She kept her eyes on the Doctor’s, and she kept sucking. Her other hand was on the Doctor’s hip. She let herself get lost in the physicality, the _perversity_ of it. She was still almost entirely fully dressed, the Doctor still had her upper body covered. The Doctor was falling apart beneath her, sighing and moaning and whimpering. She gasped every time Yaz’s teeth ran along her knuckles, or Yaz’s tongue swirled along the tip of her finger. She was shaking, and her back was arching. 

“What are you going to do?” Yaz let the Doctor’s fingers slide out of her mouth, as they stroked across her cheek, leaving a wet trail. “I’ll have to keep testing you, I’ll have to make sure that you’re safe for Earth, make sure that -”

“Ah!” The Doctor’s back arched off of the table, and then she was coming. It was an intense orgasm, evidently, judging by the way the Doctor was thrashing on the table. Her whole face was bright red, scrunched up, and her mouth was wide open. Her chest was heaving, and her eyes were squeezed shut. There was another gush, and the wetness soaked into the front of the harness, smeared across Yaz’s belly. The Doctor ended up flat on the exam table, staring at the ceiling, grinning like she knew the secrets of the universe and couldn’t wait to share. 

“How are you doing?” Yaz asked, after almost a full moment of panting, sweaty silence. “I didn’t break anything important, did I?”

“I think I squirted,” the Doctor said. “I didn’t know I could do that!” 

“Congratulations,” said Yaz, “although I think the dildo did all the heavy lifting.” She pulled out carefully, and then she… stood there, feeling awkward with an orange dildo sticking out in front of her. 

“I don’t think a dildo could do a lot of heavy lifting,” the Doctor said, and she sat up fully, her feet dangling off of the edge of the table. “It’d collapse under the weight.”

Yaz snorted, and she tried to subtly rub her thighs together. When was the last time she’d been this wet? 

“I do believe I owe you… three orgasms,” the Doctor said. 

“You don’t _owe_ me anything,” Yaz said weakly. The Doctor was getting back on her feet, and she was only wobbling a little bit.

“I mean, fair enough, don’t wanna go lookin’ at sex as if it’s some kind of transactional dealie,” said the Doctor, “but I want to give you three orgasms. At least. Probably more than that. Or not orgasms, if you don’t want orgasms. But…” She waved her hands about, looking absurd in her bare feet and two t-shirts. “I want to do things for you. To you. With you,” she said, and now she looked faintly embarrassed, but pleased with herself. 

“Right,” said Yaz. “I’d be for that. Could be… could be fun.” She paused, looked around the room. “But could we do it someplace else, maybe? Someplace with a bed?” Her knees were aching, and her back hurt from all of the thrusting.

“We have rooms in the TARDIS that are nothing _but_ beds,” the Doctor said, and she was giving one of her “light up the room” grins. She held a hand out. “Shall we?”

“I think you should put some pants on, first,” Yaz said, and she was giggling in spite of herself as she indicated the Doctor’s bare legs.

The Doctor looked down at her own body, and she made a face. “New I was forgetting something,” she said. “While I put on my horrible slimy pants, why don’t you tell me one of your deep, dark sexual secrets?”

And Yaz blushed. “Well,” she began.


End file.
